Old tuff quarries (locally known as Tufare) located to the north of the town of Nocera Inferiore, southwest of the village of Fiano (Nocera Inferiore municipality), and to the south of Lavorate (Sarno municipality).

Quarry operations evidenced metamorphosed xenoliths containg F-, B-, and Mg-rich minerals. The parental rocks of these xenoliths are Mesozoic sedimentary carbonates of the Campanian Apennines, whose fragments were randomly embedded in the pyroclastic flow during its emplacement at the Fiano site (ca. 50 km far from the eruption source). The Campanian Ignimbrite pyroclastic flow emplaced at Fiano had a temperature range of 300-500°C and underwent hydrothermal processes during its cooling.

The F-rich xenoliths within the Campanian Ignimbrite at Fiano were first described by Scacchi (1881, 1885, and 1890), vom Rath (1887), and Zambonini (1913 and 1919). The authors detected various newly formed phases, some of which subsequently discredited: it is the case of "nocerite" (Scacchi, 1881) recognised to be equal to fluoborite (Brisi & Eitel, 1957), "grothine" (Zambonini, 1913) recognised to be equal to norbergite (White, 1981), and "fluosiderite" (Scacchi, 1885) recognised to be equal to chondrodite (Balassone et al., 1995 and 2002).
The Fiano mineral assemblage is mainly represented by halides, F-, Mg- and Ca-bearing silicates, carbonates, and oxides, with subordinate borates, arsenates, and vanadates. The xenoliths exhibit different dimensions, ranging from few millimetres to several centimeters (Carati, 1987). An exceptional occurrence of a block of 2.3x1.4x0.7 m in size was described by Scacchi (1885 and 1890). According to Carati (1987), the xenoliths were initially grouped into "micaceous clasts", "fluoriferous geodes", and "weakly metamorphosed carbonate rocks". The micaceous xenoliths (1-35 cm in size) have friable mica-bearing crusts, brown to honey -yellow in colour. These rocks were considered as derived from limestone protoliths, metamorphosed to a varying extent, and often characterised by one or more crusts and a core constituted by calcite, as a relict of the primary limestone. Fluorite is widespread and pervasive, fluoborite and chondrodite are also common in the various coatings. The "fluoriferous geodes" represent the final product of the metamorphic process affecting the limestone (Masi & Turi, 1972), and are mostly composed of microcrystalline fluorite and rare calcite. The "weakly metamorphosed carbonate rocks” have variable dimensions, and can locally show fluorite-rich veinlets and voids and/or rare silicates as thin external coatings.

Regions containing this locality

Eurasian Plate	Tectonic Plate
Europe	Continent

Regional Geology

This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.

Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org

Cretaceous 66 - 145 Ma ID: 3186408	Mesozoic sedimentary rocks Age: Cretaceous (66 - 145 Ma) Lithology: Sedimentary rocks Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. [154]
Early Cretaceous 100.5 - 145 Ma ID: 3130972	Early Cretaceous limestone Age: Early Cretaceous (100.5 - 145 Ma) Lithology: Limestone Reference: Asch, K. The 1:5M International Geological Map of Europe and Adjacent Areas: Development and Implementation of a GIS-enabled Concept. Geologisches Jahrbuch, SA 3. [147]

Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License

References